Department of Integrative Physiology and The Center for Neuroscience, University of Colorado, Boulder, Colorado, United States of America.
PLoS One. 2012;7(9):e45415. doi: 10.1371/journal.pone.0045415. Epub 2012 Sep 17.
In order to further understand the genetic basis for variation in inherent (untrained) exercise capacity, we examined the brains of 32 male rats selectively bred for high or low running capacity (HCR and LCR, respectively). The aim was to characterize the activation patterns of brain regions potentially involved in differences in inherent running capacity between HCR and LCR. Using quantitative in situ hybridization techniques, we measured messenger ribonuclease (mRNA) levels of c-Fos, a marker of neuronal activation, in the brains of HCR and LCR rats after a single bout of acute treadmill running (7.5-15 minutes, 15° slope, 10 m/min) or after treadmill running to exhaustion (15-51 minutes, 15° slope, initial velocity 10 m/min). During verification of trait differences, HCR rats ran six times farther and three times longer prior to exhaustion than LCR rats. Running to exhaustion significantly increased c-Fos mRNA activation of several brain areas in HCR, but LCR failed to show significant elevations of c-Fos mRNA at exhaustion in the majority of areas examined compared to acutely run controls. Results from these studies suggest that there are differences in central c-Fos mRNA expression, and potential brain activation patterns, between HCR and LCR rats during treadmill running to exhaustion and these differences could be involved in the variation in inherent running capacity between lines.
为了进一步了解内在（未经训练）运动能力变化的遗传基础，我们检查了 32 只雄性大鼠的大脑，这些大鼠分别经过选择性繁殖以获得高或低的跑步能力（分别称为 HCR 和 LCR）。目的是描述潜在参与 HCR 和 LCR 之间内在跑步能力差异的大脑区域的激活模式。使用定量原位杂交技术，我们测量了 HCR 和 LCR 大鼠在单次急性跑步机跑步（7.5-15 分钟，15°坡度，10 m/min）或跑步机跑步至力竭（15-51 分钟，15°坡度，初始速度 10 m/min）后的大脑中神经元激活标志物 c-Fos 的信使核糖核酸（mRNA）水平。在验证特征差异时，HCR 大鼠在力竭之前的跑步距离比 LCR 大鼠远六倍，跑步时间长三倍。与急性跑步对照组相比，力竭跑步显著增加了 HCR 中多个大脑区域的 c-Fos mRNA 激活，但 LCR 在大多数检查的区域中未能显示出 c-Fos mRNA 的显著升高。这些研究结果表明，在跑步机力竭跑步期间，HCR 和 LCR 大鼠的中枢 c-Fos mRNA 表达和潜在的大脑激活模式存在差异，这些差异可能与品系之间内在跑步能力的变化有关。
